Pipe cut-off tool and accessories for such tools

ABSTRACT

Power tools such as cutting saws with rotary powered blades are described. Also described are various accessories for tools used with cylindrical workpieces such as pipes are described. The accessories include a clamp and saw joint assembly, various quick connection assemblies between a saw and a clamping system, a plunge guide assembly, a latch plate assembly, an interlock switch, a blade guard system, and a chip management system or chip deflector. Also described are related methods of use.

FIELD

The present subject matter relates to steel pipe fabrication but couldbe extended to fabrication or processing of other tubular materials.Further, the present subject matter also relates to systems where quickseparation and removal between integral parts of a system isadvantageous, or where movement around a cylindrical object is required.

BACKGROUND

A need exists for a very efficient, accurate, and easier means ofattaching a cutting saw to a clamping assembly for cylindrical pipe orworkpiece fabrication. To optimize a cutting saw system for “on theground cutting” and “in-place cutting,” separating the clamping piecesand the cutting saw components is beneficial to reduce the massotherwise required for the user to attach to the pipe. This isparticularly important when cutting in-place where the position of thepipe or workpiece may be difficult to reach and manipulating smallerparts is much simpler.

In addition, a need exists for an ability to accurately cut steel pipeof various sizes on a job site. Commonly used methods such as plasmacutting or torch cutting require significant setup time and result in acutting surface that requires additional operations, for example,grinding. Improved accurateness of the cut allows secondary fabricationprocesses such as beveling, to be applied directly following the cut,thereby eliminating the need to refine the cut end prior to thoseprocesses being applied to the workpiece.

Furthermore, a clean method of controlling the metal debris producedduring the cutting process, is needed to thereby simplify clean-up andreduce the effects of projectile chips that are distributed from theblade during the cut process.

Accordingly, a need exists for assemblies and/or strategies to promoteoperator ease when performing operations on cylindrical workpieces suchas pipes.

SUMMARY

The difficulties and drawbacks associated with previous approaches areaddressed in the present subject matter as follows.

In one aspect, the present subject matter provides a powered cut-offtool comprising a motor, a rotary cutting blade driven by the motor, andcontrol provisions for selectively adjusting operation of the motor. Thesaw also comprises at least one feature selected from the groupconsisting of (i) an alignment plate for use in a plunge guide assembly,(ii) a latch plate assembly for use in a quick connection assembly,(iii) an interlock system, (iv) a blade guard system, (v) a chipmanagement system, and (vi) combinations of (i)-(v).

In another aspect, the present subject matter provides a quick releaseassembly for attaching a pipe fabrication tool to a clamping system. Theclamping system includes a pair of pivotally moveable arms and aslideable central carriage. The quick release assembly comprises a quickconnect pin extending outward from the clamping system. The pin definesa tip, a base, and a circumferential groove extending about an outerperiphery of the pin.

In yet another aspect, the present subject matter provides a plungeguide assembly for use with a pipe fabrication tool having a rotaryblade, and a clamping system. The plunge guide assembly comprises analignment plate affixed to the pipe fabrication tool, and a groovedguide affixed to the clamping system. One of the grooved guide and thealignment plate includes an axially positionable pin, and the other ofthe grooved guide and the alignment plate includes a cylindrical bore.Upon attaching the pipe fabrication tool to the clamping system, thealignment plate is engaged with the grooved guide by axial positioningof the pin in the cylindrical bore.

In still another aspect, the present subject matter provides a latchplate assembly for use with a pipe fabrication tool having a rotaryblade and a receiving aperture, and a clamping system with a quickconnect pin extending outward from the clamping system. The pin definesa circumferential groove extending about an outer periphery of the pin.The latch plate assembly comprises a positionable latch plate providedon the pipe fabrication tool. The latch plate defines a concave cutout.Upon insertion of the quick connect pin in the receiving aperture, theconcave cutout of the latch plate engages the quick connect pin.

In yet another aspect, the present subject matter provides an interlocksystem for use with a pipe fabrication tool having a rotary blade anddefining a receiving aperture, and a clamping system with a quickconnect pin. The interlock system comprises an electrical switch. Uponinsertion of the quick connect pin in the receiving aperture, theelectrical switch is closed to thereby allow operation of the pipefabrication tool.

In another aspect, the present subject matter provides a chip managementsystem for use with a pipe fabrication tool having a rotary blade. Thechip management system comprises a blade guard positioned adjacent therotary blade of the pipe fabrication tool. The blade guard includes anexit and at least one diverging wall extending toward the exit. The chipmanagement system also comprises at least one primary channel defined inthe pipe fabrication tool extending between the exit of the blade guardand a region in the pipe fabrication tool for dispelling chips generatedduring blade operation.

In another aspect, the present subject matter provides a blade guardsystem for use with a pipe fabrication tool having a rotary blade. Theblade guard system includes a forward blade guard positionable about anaxis of rotation of the blade, and a rearward blade guard alsopositionable about the axis of rotation of the blade.

As will be realized, the subject matter described herein is capable ofother and different embodiments and its several details are capable ofmodifications in various respects, all without departing from theclaimed subject matter. Accordingly, the drawings and description are tobe regarded as illustrative and not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective schematic illustration of an embodiment of aclamp and saw joint assembly in accordance with the present subjectmatter.

FIG. 2 illustrates the clamp and saw joint assembly of FIG. 1 in ajoined configuration.

FIG. 2A is an exploded assembly view of the clamp and saw joint assemblyof FIG. 1 in association with a typical clamping system.

FIG. 3 illustrates an embodiment of a chip deflector in accordance withthe present subject matter.

FIG. 4 illustrates an embodiment of a quick connect pin assembly inaccordance with the present subject matter.

FIG. 5 illustrates engaging a saw to a clamping assembly using the quickconnect pin assembly of FIG. 4.

FIG. 6 illustrates an embodiment of a saw connection latch plateassembly in accordance with the present subject matter.

FIG. 7 illustrates details of another embodiment of a quick connect pinin accordance with the present subject matter.

FIG. 8 illustrates details of an embodiment of a plunge guide assemblyused in the clamp and saw joint assembly of the present subject matter.

FIG. 9 illustrates the clamp and saw joint assembly of FIG. 8 with thesaw in a “ready” position.

FIG. 10 illustrates details of an embodiment of an interlock system inaccordance with the present subject matter.

FIG. 11 illustrates an embodiment of a blade guard system in accordancewith the present subject matter.

FIG. 12 illustrates the blade guard system of FIG. 11 in a configurationin which a saw blade is completely guarded.

FIG. 13 illustrates the blade guard system of FIG. 11 upon saw rotationand opening of a rearward guard.

FIG. 14 illustrates the blade guard system of FIG. 11 in a configurationin which a saw blade is depicted cutting a pipe.

FIG. 15 illustrates the blade guard system of FIG. 11 with a saw at a“plunged” position.

FIG. 16 illustrates details of an embodiment of a chip management systemwith a chip channel provided in a saw in accordance with the presentsubject matter.

FIG. 17 illustrates an embodiment of a chip management system with asecondary chip channel in a saw with a cover installed, in accordancewith the present subject matter.

FIG. 18 illustrates the chip channel of FIG. 17 with the cover removed.

FIG. 19 illustrates additional details of the chip management systemwith the chip channel of FIG. 17, showing an initial exit open.

FIGS. 20A-20D illustrate an embodiment of a horizontal spring pinassembly in association with a clamp and saw joint assembly inaccordance with the present subject matter.

FIGS. 21A-21G illustrate an embodiment of a selectively positionablespring pin assembly in association with a clamp and saw joint assemblyin accordance with the present subject matter.

FIGS. 22A-22E illustrate an embodiment of a slotted assembly inassociation with a clamp and saw joint assembly in accordance with thepresent subject matter.

FIGS. 23A-23H illustrate an embodiment of a swivel clamp connection inassociation with a clamp and saw joint assembly in accordance with thepresent subject matter.

FIGS. 24A-24K illustrate an embodiment of a spring pin connection inassociation with a clamp and saw joint assembly in accordance with thepresent subject matter.

FIGS. 25A-25D illustrate an embodiment of a dovetail joint connection inassociation with a clamp and saw joint assembly in accordance with thepresent subject matter.

FIGS. 26A-26C illustrate an embodiment of a shaft clamp connection inassociation with a clamp and saw joint assembly in accordance with thepresent subject matter.

FIGS. 27A-27D illustrate an embodiment of a toggle clamp connection inassociation with a clamp and saw joint assembly in accordance with thepresent subject matter.

FIGS. 28A-28I illustrate an embodiment of a cam locking connection inassociation with a clamp and saw joint assembly in accordance with thepresent subject matter.

FIGS. 29A-29B illustrate another embodiment of a cam locking connectionin association with a clamp and saw joint assembly in accordance withthe present subject matter.

FIGS. 30A-30B illustrate an embodiment of a twin cam locking knobconnection in association with a clamp and saw joint assembly inaccordance with the present subject matter.

FIGS. 31A-31D illustrate an embodiment of a cam knob and pin connectionin association with a clamp and saw joint assembly in accordance withthe present subject matter.

FIGS. 32A-32B illustrate an embodiment of a spring loaded leverconnection in association with a clamp and saw joint assembly inaccordance with the present subject matter.

FIG. 33 illustrates an embodiment of a spring loaded knob connection inassociation with a clamp and saw joint assembly in accordance with thepresent subject matter.

FIGS. 34A-34B illustrate an embodiment of a spring biased quick releasepin connection in association with a clamp and saw joint assembly inaccordance with the present subject matter.

FIGS. 35A-35C illustrate an embodiment of a hook connection inassociation with a clamp and saw joint assembly in accordance with thepresent subject matter.

FIGS. 36 and 37 illustrate an embodiment of a cutting saw assemblyhaving various accessories described herein.

FIGS. 38 and 39 illustrate the saw assembly of FIGS. 36 and 37 inconjunction with a clamping assembly, a saw joint assembly, and aworkpiece, in which the saw is at a “ready” position.

FIGS. 40 and 41 illustrate the saw assembly of FIGS. 38 and 39 in whichthe saw is at a “plunged” position.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present subject matter provides powered cut-off tools, moreparticularly powered rotary tools and in particular powered pipefabrication tools or rotary saws. The present subject matter alsoprovides various accessories for tools used with cylindrical workpiecessuch as pipes. In particular, the present subject matter providesaccessories for clamping systems and pipe cutting saws. Theseaccessories include a clamp and saw joint assembly between the saw and aclamping system, quick connection assemblies between the saw and aclamping system, a plunge guide assembly, an interlock switch assembly,a blade guard system, and a chip management system and/or chipdeflector. Each of these accessories can be used independently orsolely, or in various combinations. Details of these and other aspectsare set forth herein. Although the term “saw” is used herein, it will beunderstood that the term includes other tools and/or operations forsevering workpieces such as grinders for grinding and cut-off wheels forsevering or removing workpiece material.

To more easily attach a saw to a clamp or clamping assembly for a pipeor workpiece, the present subject matter provides a detachable saw jointassembly between the clamping system and the saw portion of theassembly. In this manner, a user can position the clamp or clampingassembly onto the pipe or workpiece without the additional weight andcomponents of the cutting saw and tighten the clamp onto the pipe. Theuser can then attach the saw portion of the tool to the clamp portionand complete the cut as desired. This saw joint assembly can utilizecommon fasteners, for example, hex head cap screws, that require toolsto remove and install or can be configured using tool-free methods ofremoval or installation. One such method of a tool-free quick connectionbetween the clamp and saw portions of the tool features alignment pinson either the saw base or the clamp base, and alignment holes on theopposite component positioned such that the alignment pins are coaxialto the alignment holes when the saw is properly placed relative theclamp. To use, the operator would install the clamp onto the pipeworkpiece, align a cut indicator with the desired line of cut, and thenlower the saw base onto the clamp base with the alignment pins engagingthe alignment holes. The operator would then tighten one or morethreaded knobs to complete the alignment of the saw base to the clampbase and adequately fix the saw to the clamp. The threaded knobs couldbe configured such that they are retained to the saw base via the use ofa counterbored opening.

FIGS. 1, 2, and 2A illustrate an embodiment of a clamp and saw jointassembly 10 in accordance with the present subject matter. The clamp andsaw joint assembly (or “saw joint assembly” as periodically referred toherein) is illustrated in use with a clamping system such as describedin U.S. application Ser. No. 16/591,753 filed Oct. 3, 2019. FIG. 2A isan exploded assembly view of the saw joint assembly of FIGS. 1 and 2 inconjunction with the noted clamping system generally denoted as 2. Theclamping system 2 comprises a base 2B having a threaded member orregion. Typically, the threaded region is in the form of a female boreor aperture having helical thread(s). The clamping system 2 alsocomprises a pair of arms including a first arm 2C defining a proximalend and an opposite distal end. The first arm 2C also defines a guideslot extending at least partially between the ends. The pair of armsalso includes a second arm 2D defining a proximal end and an oppositedistal end. The second arm 2D also defines a guide slot extending atleast partially between the ends. In many versions, one or more rollersare provided at or near the distal ends of the arms. For example, afirst roller is provided at the distal end of the first arm, and asecond roller is provided at the distal end of the second arm. Each armcan utilize a plurality of rollers. The first and second arms 2C, 2D arepivotally supported and secured to the base 2B. The clamping system 2also comprises a shaft 2E defining a proximal end and an opposite distalend. The shaft 2E also defines a threaded region. The shaft 2E isthreadedly engaged with the base 2B via the threaded region of the base.The clamping system 2 also comprises a slideable central carriage 2A.The central carriage 2A includes a central roller or plurality ofrollers rotatably secured thereto. The central carriage 2A is rotatablyaffixed to the distal end of the shaft 2E such that the shaft canundergo rotation without transfer of such rotation to the centralcarriage 2A. The central carriage 2A is movably retained to the pair ofarms, i.e., the first arm and the second arm as described herein.Additional details and aspects of the clamping system 2 are provided inthe noted application.

Referring further to FIGS. 1, 2, and 2A, the saw joint assembly 10comprises a clamp base 20 which is secured to the clamping system 2, anda separable or selectively removable saw base 40. In the particulardepicted version of the saw joint assembly 10, the clamp base 20includes one or more outwardly extending alignment pins 22 projectingfrom an engagement face 24 of the clamp base 20. The clamp base 20 alsoincludes one or more tapped or threaded aperture(s) 26 accessible alongthe engagement face 24 of the clamp base 20. Typically, the alignmentpin(s) 22 and the threaded aperture(s) 26 extend transversely to theplane of the engagement face 24. However, the present subject matterincludes variations and alternate configurations. The saw base 40defines at least one alignment aperture(s) 42 in an engagement face 44.The engagement face 44 of the saw base 40 is directed toward theengagement face 24 of the clamp base 20 and upon joining the bases 20,40 together, the engagement face 44 of the saw base 40 contacts theengagement face 24 of the clamp base 20. The alignment aperture(s) 42 ofthe saw base 40 are located and positioned in the saw base 40 such thatupon joining the bases 20, 40 together, the alignment pin(s) 22 of theclamp base 20 extend within the alignment aperture(s) 42 of the saw base40. Thus, the alignment aperture(s) 42 are also sized and shaped tofittingly receive and engage the corresponding alignment pin(s) 22 ofthe clamp base 20. Typically, the alignment apertures 42 extendtransversely to the engagement face 44 of the saw base 40. However, thepresent subject matter includes variations and alternate configurations.

Upon joining the saw base 40 to the clamp base 20 by contacting theirrespective engagement faces 44 and 24, and inserting the alignmentpin(s) 22 into the alignment aperture(s) 42, the saw base 40 can beselectively retained or affixed to the clamp base 20 by one or morefasteners such as threaded knob(s) 46 with projecting threaded member(s)47. In certain versions, the threaded knobs 46 and members 47 arerotatably retained with the saw base 40. The threaded knobs 46 arepositioned and located on the saw base 40 such that upon joining the sawbase 40 to the clamp base 20, the threaded member(s) 47 are threadedlyreceived by the tapped or threaded apertures 26 of the clamp base 20.Thus, as will be understood, the threaded member(s) 47 of the threadedknob(s) 46 extend from the engagement face 44 of the saw base 40.Typically, the threaded member(s) 47 extend transversely from the face44. However, the present subject matter includes variations andalternate configurations. The knob(s) 46 are typically accessible alonga proximal face 48 of the saw base 40 which is oppositely directed fromthe engagement face 44 of the saw base 40.

The saw joint assembly 10 is positionable between an unjoinedconfiguration as shown in FIG. 1, and a joined configuration such asdepicted in FIG. 2 in which the engagement face 24 of the clamp base 20contacts the engagement face 44 of the saw base 40, the at least onealignment pin 22 of the clamp base 20 is disposed in the at least onealignment aperture 42 of the saw base 40, and the at least one threadedmember 47 of the saw base 40 is threadedly engaged with the at least onethreaded aperture of the clamp base 20.

The knob(s) 46 of the saw base 40, accessible along the proximal face 48of the saw base 40, can be rotated to thereby further engage and tightentheir corresponding threaded member(s) 47 with the tapped aperture(s) 26of the clamp base 20. This serves to selectively retain and affix thesaw base 40 to the clamp base 20.

The clamp base 20 typically includes a mounting region 30 for affixingor securing to a clamping system such as clamping system 2. The mountingregion 30 can be integrally formed with the clamp base 20 or affixedthereto. As will be understood, the clamp base 20 and/or the mountingregion 30 is typically affixed or secured to a clamping system by one ormore threaded fasteners 32. The clamp base 20 also defines alongitudinal slot 34 extending through the clamp base and accessiblealong the engagement face 24. The longitudinal slot 34 is sized andshaped to receive a saw blade (not shown) inserted or positionedtherein. The saw base 40 also defines a longitudinal slot 54 extendingthrough the saw base 40. The longitudinal slot 54 is sized and shaped toreceive a saw blade (not shown) inserted or positioned therein. Thelongitudinal slot 34 of the clamp base 20 is positioned and located inthe clamp base 20 and/or the longitudinal slot 54 of the saw base 40 ispositioned and located in the saw base 40 such that upon joining thebases 20, 40 together, the longitudinal slots 34, 54 are aligned witheach other. Thus, the orientation of the slots 34, 54 is such that a sawblade can extend through both slots 34, 54.

In certain versions, the present subject matter also provides a chipdeflector that collects and deflects metal chips that have been removedfrom the pipe during the cutting process and prevents the chips fromhitting the operator or bystanders. As the cutting blade passes throughthe pipe, small metal chips, typically equivalent to the width of thecutting blade, are removed and pushed out and away from the pipe orworkpiece in the direction of the cutting blade rotation at relativelyhigh velocity. A deflector is provided such that these chips are slowedand redirected towards the workpiece and tool, where secondaryredirections further reduce velocity and position the chips to fallclose to the workpiece being cut, rather than projecting far away fromthe workpiece. This deflector can be configured to work with all pipesizes within the range of application for the clamp/saw.

In many embodiments, the chip deflector can also be pivoting and biasedtowards the pipe to minimize the gap through which chips can be ejected.Alternatively, a flexible chip deflector (not shown) can be configuredto always contact the circumference of the pipe to be cut. However, thepresent subject matter includes variations and alternate configurations.

FIG. 3 illustrates an embodiment of a chip deflector 60 in accordancewith the present subject matter. FIG. 3 depicts the chip deflector 60 inassociation with the previously described saw joint assembly 10 used inconjunction with the noted clamping assembly 2. The chip deflector 60includes one or more walls 66 for deflecting and redirecting metalchips. The chip deflector 60 defines an entrance 62 for providing accessto an interior region defined by the walls 66. The deflector 60 alsodefines an exit 64. The chip deflector 60 is releasably secured to thesaw joint assembly 10 and particularly to either the clamp base 20 orthe saw base 40. The deflector 60 is positioned relative to the sawjoint assembly 10 such that metal chips generated and dispelled during acutting or processing operation, enter the deflector 60 such as throughentrance 62, contact the wall(s) 66, and exit the deflector 60 throughexit 64.

In addition to the aspects and features described herein, a quickconnection assembly can be used conveniently and quickly engaging thesaw portion of the assembly to the clamp portion. A preferred embodimentof the quick connect assembly is shown in FIG. 4. This embodimentfeatures a large pin with a conical region and tip and circumferentialgroove that performs two functions: locking the saw portion of theassembly to the clamp portion and providing a pivoting axis around whichthe saw portion rotates to provide blade penetration to completely cutthrough the wall of the pipe or workpiece. In certain embodiments, thepresent subject matter further includes a grooved guide opposite thepin. These aspects are described in greater detail herein.

Specifically, FIG. 4 illustrates a quick connect pin 70 mounted to acentral carriage 2A or like component of the clamping system 2. Thequick connect pin 70 defines a distal tip 72, a cylindrical base 74, anda conical transition region 76 between the tip 72 and the base 74. Thepin 70 further defines a circumferential groove 78 extending about theouter periphery of the pin 70. Typically, the groove 78 is locatedwithin the base 74 or between the base 74 and the conical region 76.Typically, the pin 70 extends from the central carriage 2A in adirection parallel to a longitudinal axis of a workpiece 4 to which theclamping system 2 is engaged.

FIG. 4 also illustrates an optional grooved guide 90 provided inassociation with the clamping system 2 and particularly the centralcarriage 2A. The grooved guide is described in greater detail herein inassociation with a plunge guide assembly having an alignment plateillustrated in FIG. 8.

To attach the saw unit to the clamp, the user would align a main pivotbore of the saw unit to the axis of the quick connect pin of the clamp,then slideably install the saw unit onto the pin, as depicted in FIG. 5.Specifically, FIG. 5 illustrates a clamping system 2 having the quickconnect pin 70 previously described in conjunction with FIG. 4, and asaw assembly 100.

The conical region and tip of the quick connect pin act to open a latchplate integral to the saw unit. The latch plate is spring-biased to anengaged position, but a generous lead-in chamfer of the conical tip ofthe quick connect pin acts to compress the biasing spring and allow thelatch pin to rotate about a fixed pivot point. In this manner, there isno user input required to latch the saw unit to the clamp unit. Thelatch plate movement occurs through the sliding installation of the sawunit to the clamp. When installed, a concave cutout in the latch pinengages the circumferential groove in the quick connect pin, locking thesaw unit and clamp unit together.

FIG. 6 illustrates an embodiment of a positionable latch plate 110 of asaw assembly 100 engaged with the previously described quick connect pin70. The latch plate 110 is pivotally positionable about a pivot member112. A spring or other biasing member 114 is provided to urge the latchtoward an engaged position as shown in FIG. 6. The latch plate 110defines a cutout 116, which is preferably a concave cutout, sized andshaped to fittingly engage and particularly be disposed in, thecircumferential groove 78 (see FIG. 4) of the pin 70. The cutout engagesthe groove to thereby restrict axial movement. The present subjectmatter also includes assemblies in which the cylindrical bore of thealignment plate is axially positioned with the pin to engage the pin inthe bore.

To remove the saw unit from the clamp, the user would depress a latchplate manual release point to pivot the latch plate concave cutout outof engagement with the circumferential groove of the quick connect pin,then slideably translate the saw unit along the axis of the quickconnect pin to separate.

The quick connect pin of the clamping system is optimally configured toutilize two different diameters that engage corresponding bored surfaceson the saw unit. These different diameters improve the ease of useinstalling or disassembling the saw unit from the clamping unit by morequickly separating the tight clearance bore and shaft faces compared toa single diameter interface. The transition between the two differentdiameters can be achieved in many ways, but in many embodiments, thepresent subject matter provides a tapered transition. Likewise, theinterface between the quick connect pin of the clamp and the pivot boreof the saw unit is optimally configured using bushings or bearings thatpromote easy axial installation and rotation during use, and preventinggalling or other surface wear that is possible in this connection. Itwill be understood that the quick connect pin could also utilize twodifferent cross sectional shapes such as a first region having a squareshaped cross section and a second region having a round or circularcross section. In addition or alternatively, the quick connect pin coulduse two or more regions having different sizes or cross sectional spans.

FIG. 7 illustrates another embodiment of a quick connect pin 70utilizing two different diameters for engaging corresponding boredsurfaces or apertures on a saw unit. In this version, the pin 70 definesa first circumferential region 71 having a first diameter D₁, a secondcircumferential region 73 having a second diameter D₂ which is greaterthan D₁, and a tapered transition region 75 extending between theregions 71 and 73. Typically, the previously described groove 78 isbetween the two regions 71, 73 having different diameters. And incertain versions, the groove 78 is also between the first region 71 andthe transition region 75.

When the saw unit is properly installed onto the quick connect pin, thesaw unit can be rotated on the quick connect pin of the clamping systemuntil an alignment plate on the saw unit engages the grooved guide ofthe clamp. The tightly toleranced grooved guide accepts the alignmentplate and controls the orientation of the saw unit to the clamp toensure efficient and accurate use of the tool without misalignment whencutting the workpiece.

FIG. 8 illustrates an embodiment of a plunge guide assembly including analignment plate 120 attached to the saw assembly 100. The alignmentplate 120 engages the grooved guide 90 noted in association with FIG. 4.The grooved guide 90 is affixed or otherwise secured to the clampingsystem 2 and particularly the central carriage 2A. The plunge guideassembly comprises the alignment plate 120 and the noted grooved guide90.

As the saw unit is rotated such as about the quick connect pin, an entryslot on the alignment plate of the saw unit depresses a spring-biaseddepth lock pin on the clamp until the depth lock pin reaches acylindrical bore that allows the spring-biased pin to extend and lockthe saw in position. In this manner, the saw unit is fully assembled tothe clamp without requiring user input to lock it in place, and ispositioned in a “ready” position for use.

FIGS. 8 and 9 illustrate engagement between the alignment plate 120 ofthe saw 100 and the grooved guide 90 of the clamping system 2. Thealignment plate 120 defines an entry slot 122 providing access to acylindrical bore (not shown). The guide groove 90 includes an axiallypositionable depth-lock pin 92. The pin 92 is typically biased to anengaged position. Upon engaging the alignment plate 120 and the guidegroove 90, the entry slot 122 depresses or otherwise actuates the pin 92so the pin 92 engages the cylindrical bore in the alignment plate 120 tothereby lock the saw 100 in a fixed position relative to the clampingsystem 2.

To cut through the pipe wall, the user actuates the power supply of thetool to begin cutting blade rotation, then retracts the depth lock pinto disengage the pin from the ready-position bore of the saw unit. Theuser would rotatably guide the saw unit to cut through the pipe walluntil the depth lock pin engages the plunged-position bore of thealignment plate. When this engagement occurs, the saw unit has reachedits maximum plunge rotational travel and is locked in place. The usercan then guide the saw unit around the pipe circumferentially toseparate the workpiece.

The present subject matter also provides the use of an interlock switchassembly that prevents use of the cutting head when the saw unit is notmechanically attached to the clamping system. While there are many waysof achieving this, a preferred embodiment utilizes a micro switch thatelectrically interrupts/disconnects the power supply from the saw motorwhen the quick connect pin is not installed through the main pivot boreof the saw unit. When the quick connect pin is engaged by the saw, anactuating paddle is pivoted to engage the interlock switch, closing theelectrical circuit and allowing tool use. Thus, in many versions, withinsertion of the saw to the clamping system through a receiving feature,the electrical switch is closed to thereby allow operation of the saw.

FIG. 10 illustrates an embodiment of an interlock system 130 inaccordance with the present subject matter. The interlock system 130 isincorporated in a saw assembly 100 that includes a receiving aperture102 or main pivot bore sized and shaped to receive and accept the quickconnect pin 70. The interlock system 130 comprises a positionable paddle132 having an engagement end 134 and a working end 136. The paddle 132can be pivotally mounted to the saw assembly 100 via a pin 138 or likemember. The interlock system 130 also comprises an electrical switch 140with a lever contact(s) 142 positionable between an open state and aclosed state occurring when the quick connect pin 70 is inserted withinthe receiving aperture 102 thereby moving the paddle 132 to causeclosure of the switch contacts 142 and thereby complete the electricalcircuit. It will be understood that FIG. 10 illustrates two positionsfor the lever contact 142, an open position and a closed position.

The present subject matter also provides a blade guard system. The sawunit features a plurality and typically two blade guards that pivotaround the same axis as the saw cutting blade. The blade guards arespring-biased to a closed position shown in FIG. 11, with an optionalstop controlling the limit of their rotational travel. Optimally, asingle spring is used to bias the guards towards each other and preventuser access to the blade. In another embodiment, two separate springscould be used to independently control each blade guard. The stop isideally comprised of a rubber material to reduce wear on the guards.

Specifically, FIGS. 11 and 12 illustrate an embodiment of a blade guardsystem 150 in accordance with the present subject matter. The bladeguard system 150 is incorporated in a saw assembly 100 with a rotaryblade 101 and comprises a forward blade guard 152 and a rearward bladeguard 154. The forward blade guard 152 and the rearward blade guard 154pivot about the axis of rotation of the saw blade 101, shown as axis A.As previously described, one or more springs or other biasing membersare used to bias the guards 152, 154 to their closed position as shownin FIG. 11. Thus, the blade guards when closed reduce access to the sawblade 101. The blade guard system 150 can include a stop 156 thatcontrols or limits the extent of rotational travel of the guards 152,154 about axis A.

Referring further to FIG. 12, when the saw unit 100 is being installedonto the clamping system 2, the spring-biased forward and rearward bladeguards 152, 154 cover the teeth of the blade 101 that would otherwiseextend from the saw 100.

Referring to FIG. 13, as the user rotates the saw unit 100 about thequick connect pin 70 to reach the “ready” position of the saw unit, therearward blade guard 154 makes contact with the outer diameter of thepipe 4 via a raised fin 155 along the outside profile of the guard 154.This fin 155, along with a similar fin 153 on the forward blade guard152, is configured such that the pivoting motion of the saw 100 urges orotherwise displaces the blade guards 152, 154 to open, against thespring-bias, to allow the blade 101 to contact the pipe 4 surface. FIG.13 illustrates the initial opening of the rearward blade guard 154 dueto this contact with the saw in the “ready” position.

Referring to FIG. 14, when the user intends to cut the pipe 4, the sawblade is engaged with the pipe 4 and the user rotatably moves the saw100 to plunge the blade 101 into the pipe 4 wall. With this additionalplunge rotation, the rearward blade guard 154 continues to pivot openfurther, and the fin 153 on the forward blade guard 152 similarly causesthe forward blade guard 152 to rotate about its pivot and further exposethe saw blade 101 for adequate contact into the pipe wall.

Referring to FIG. 15, the saw blade guard rotation continues until thesaw 100 reaches the fully plunged position. At this position, andthroughout the positions previously described, the teeth of the blade101 are covered from direct contact by the end user; the only exposureof cutting blade teeth occur inside the pipe 4. Further, the pivotingmotion of the forward and rearward blade guards 152, 154 about the sameaxis as the cutting blade 101 is ideal as it prevents inadvertentmovement of the guard by wedging, or linear movement, between the pipe 4and the saw 100. Restated, the pivoting motion of the guards 152, 154prevents access to the blade 101 between the pipe 4 and saw 100. Thusattempting to open the guards in this area will be unsuccessful.

The present subject matter also provides a system for chip managementfor optimum saw use. In this embodiment, the forward blade guardfeatures a diverging profile opening that allows chips to exit the bladeteeth after the chips are created through the pipe wall. Restated, theblade guard profile does not have a circular profile with centerposition coaxial with the blade, thereby creating more radial distancebetween the blade and the guard as the chips move from the pipe orworkpiece. Further, the housing of the saw is configured with a largechip exit channel that directs chips out of the main saw blade housingquickly, thereby reducing the number of chips recycled around thehousing.

Referring to FIG. 16, an embodiment of this chip management system 160incorporated in a saw 100 is shown. The chip management system 160comprises a blade guard 162. The blade guard 162 is positioned near oralongside the rotary blade 101 of the saw 100. The blade guard 162differs from the previously described forward blade guard 152 in thatthe blade guard 162 utilizes an interior region with one or morediverging wall(s) 164 that extend toward an exit 166 directed away fromthe saw blade 101. The reference to diverging wall(s) refers to a wallorientation that diverges away from the blade circumference. Inaddition, the chip management system 160 comprises one or more primarychannels(s) 168 defined within or by the body or enclosure of the saw100. These channel(s) 168 are configured, i.e., sized, shaped, and/ororiented, to direct chips out of the saw 100. Specifically, the channel168 extends between the exit 166 of the blade guard 162 and an opening163 in the saw 100 for dispelling chips.

In certain embodiments, as chips reach the exit channel, they enteranother channel 169 on the opposite side of the saw or similar tool. SeeFIG. 17 and FIG. 18 which illustrate this channel 169 with and withoutthe protective covers installed, respectively. Specifically, FIGS. 17and 18 show the saw 100 with a secondary channel 169 within the body orenclosure of the saw 100. A port 172 or other opening providescommunication for chip flow from the previously described primarychannel 168 to the secondary channel 169. One or more protectivecover(s) 170 can be used to enclose the channel 169.

In this manner, high velocity chips are slowed through the change indirection induced by the exit channels. That is, in many embodimentsturning or altering chip direction is important to slow chip velocity.Likewise, the chips are directed back towards the pipe or workpiece,thereby reducing their projection towards the operator. Thisconfiguration helps control the chip path and improves clean-up effortrequired by limiting the extent of chip positions after exiting thetool.

For some pipe materials, for example polymeric materials, the separatedchip segments tend to group together after exiting the blade and coolingdown. For these materials, it is ideal to even more quickly dispel thechips from the saw unit. Therefore, an optional deflection door isconfigured such that, when open, allows these materials to exit the sawunit system earlier than the entire channel distance. Further, thislarger opening reduces the likelihood of these chips conglomerating ontoobstructions and clumping.

FIG. 19 illustrates an embodiment of a selectively positionabledeflection door 174 that provides access to the port 172 and/or theprimary and/or secondary channels 168, 169 in the saw 100. As will beunderstood, upon opening the door 174 such as shown in FIG. 19, accessand early exit from the saw 100 for chips is provided. A wide array ofassemblies can be used for selective positioning of the door 174, suchas a hinge assembly 176. However, the present subject matter includesvariations and alternate configurations.

In addition, in certain versions the present subject matter provides achip deflector as previously described herein as an alternative or inaddition to the chip management system.

The present subject matter also provides a method of quickly attachingand detaching the saw to/from the clamping system, which can be achievedthrough many various assemblies. One such alternative features springpins mounted to either the saw base or clamp base that guide into holesin the opposite piece (saw base or clamp base) to hold the saw fixed tothe clamp. Details of spring pins and other assemblies and particularlyassemblies for selectively engaging and/or retaining a clamp base 20with a saw base 40 are described herein.

Additional Aspects

FIGS. 20A-20D illustrate an embodiment of a spring pin assembly 180. Thespring pin assembly 180 is incorporated in the clamp base 20 and the sawbase 40 of the saw joint assembly 10. The spring pin assembly 180comprises at least one axially positionable member biased to extendaxially such as a first spring pin 182 and a second spring pin 184. Thefirst spring pin 182 is mounted or otherwise secured to a first mountingaperture region 183 of the clamp base 20. The second spring pin 184 ismounted or otherwise secure to a second mounting aperture region 185 ofthe clamp base 20. The saw base 40 defines a first receiving aperture186 and a second receiving aperture 188. The receiving apertures 186,188 are configured to receive corresponding engagement member(s) of thespring pins 182 and 184. As will be understood, the spring pins 182, 184include axially positionable members, typically biased to extend axiallyinto an engagement position. Upon engagement and proper alignment of theclamp base 20 and the saw base 40, the members of the spring pins 182,184 align with and are biased to axially extend into engagement with thereceiving apertures 186, 188. As noted, the present subject matterincludes embodiments in which one or more of the spring pins areprovided on the saw base 40 instead of the clamp base 20. The presentsubject matter includes orienting the spring pins and receivingapertures at different orientations besides a horizontal orientation asshown in the referenced figures.

Another such assembly utilizes a spring pin that allows the saw base topivot in position relative to the clamp base, then the two are heldsecurely using a threaded knob at the opposite end. However, the presentsubject matter includes variations and alternate configurations.

FIGS. 21A-21G illustrate an embodiment of a selectively positionablespring pin assembly 200. The assembly 200 is utilized in associationwith a clamp base 20 and a saw base 40. The assembly 200 comprises anaxially positionable member biased to extend axially such as a springpin 202. The assembly 200 also includes a receiving aperture 203 in theclamp base 20 configured to receive and engage the member of the springpin 202. The spring pin 202 is depicted as mounted on the saw base 40but could be mounted on the clamp base 20 with appropriate relocation ofthe receiving aperture in the saw base 40. The spring pin assembly 200also comprises a hinge assembly 204 having a hinge member 206. The hingeassembly 204 moveably retains the saw base 40 to the clamp base 20. Thehinge assembly 204 enables the saw base 40 to be selectively positionedabout a hinge axis 208 defined by the hinge member 206. Although a widearray of assemblies can be used for the hinge assembly 204, a preferredversion is depicted in the referenced figures in which the clamp base 20includes at least one outwardly projecting hinge finger 210 and the sawbase 40 includes at least one outwardly projecting hinge guide 212. Aswill be understood, each of the hinge finger 210 and the hinge guide 212define an aperture 211, 213 through which the hinge member 206 extendsupon assembly of the saw base 40 to the clamp base 20. A slotted openingon the saw base 40 can allow a threaded connector, integral to orotherwise associated with the clamp base, to engage and hold the tworigidly together when inserted and tightened.

FIGS. 22A-22E illustrate an embodiment of a slotted assembly 220 for thesaw joint assembly 10. The slotted assembly 220 utilizes one or moreslots 224 provided in the saw base 40, one or more threaded apertures226 in the clamp base 20, and one or more threaded members 222 extendingin the slots 224 and threadedly engaging the threaded apertures 226 ofthe clamp base 20. As will be understood, in this embodiment, a userattaches a saw (not shown) to the saw base 40 and laterally slides thesaw base 40 into position on the clamp base 20 by aligning the slots 224of the saw base 40 with the threaded members 222 of the clamp base 20.Upon proper alignment and insertion of the members 222 in the slots 224as shown in FIG. 22D, the members 222 can be tightened to therebyreleasably secure the saw base 40 to the clamp base 20.

Swivel clamps can similarly be used to rotate and engage the two basesin contact, as shown in FIGS. 23A-23H. Specifically, FIGS. 23A-23Hillustrate an embodiment of a swivel clamp assembly 250 in accordancewith the present subject matter. The swivel clamp assembly 250 isutilized to affix or otherwise engage a clamp base 20 with a saw base40. The swivel clamp assembly 250 comprises one or more and particularlya plurality of swivel clamps 260. Each swivel clamp 260 is typicallypivotally or moveably secured to the clamp base 20 at a base 262 of theswivel clamp 260. The saw base 40 includes one or more receiving slots264 adapted for receiving a corresponding swivel clamp 260. As will beunderstood, the saw base 40 can be releasably affixed or secured to theclamp base 20 by positioning the saw base 40 relative to the clamp base20 such that the receiving slots 264 are aligned with the swivel clamps260, and then contacting the bases 20, 40. Each swivel clamp 260 is thenpivoted or otherwise positioned such that it extends through itscorresponding slot 264, and a head or gripping member 266 of the swivelclamp is disposed on and in contact with the saw base 40. Instead of anintegral head or gripping member 266, the present subject matter alsoincludes adjustable threaded fasteners such as shown as 267. It will beunderstood that the arrangement of components can be reversed so thatthe swivel clamps 260 are pivotally secured to the saw base 40 and arereceived in slots in the clamp base 20.

Spring pins mounted to one of the base panels can be used to engage aclearance hole in the opposite base panel to hold the saw base to theclamp base, as shown in FIGS. 24A-24K. Specifically, FIGS. 24A-24Killustrate an embodiment of a spring pin assembly 270 used inassociation with the saw joint assembly of the present subject matter.The spring pin assembly 270 is used to affix or otherwise engage a clampbase 20 with a saw base 40. The spring pin assembly 270 comprises one ormore spring pins 272. Each spring pin 272 includes an axiallypositionable member 274 and a spring 276 or other biasing membertypically configured to urge the member 272 axially outward. Each springpin 272 can also include a handle 278. The spring pins 272 are typicallylocated along an engagement face 44 of the saw base 40. The clamp base20 includes a plurality of access ports 280 sized and located to receivethe spring pins 272 such that upon contacting and engaging the bases 20,40 together, the spring pins 272 extend through and are accessible alongthe clamp base 20. FIGS. 24G-24K depict a variation of a spring pinassembly 270 in which a user aligns protrusions on the saw base 40 toopenings on the clamp base 20, then slides the saw and corresponding sawbase to engage features that hold the two in contact while a pin isinserted. The pin, then, locks the two components together.

A dovetail joint incorporated into the saw base and clamp base can beused to hold the two components together, then a screw used to maintainjoint tension and prevent inadvertent separation, as shown in FIGS.25A-25D. Specifically, FIGS. 25A-25D illustrate aspects of an embodimentof a dovetail joint assembly 280 in association with a saw jointassembly of the present subject matter. The dovetail joint assembly 280includes a dovetail component 282 and an axially positionable adjustingmember 284, which can for example be in the form of a threaded memberthat is threadedly engaged in a threaded aperture in the clamp base 20.FIG. 25B presents a different orientation for the axially positionableadjusting member (like described for FIG. 25A) that could alternativelywork with this dovetail joint-style attachment.

The entire saw base could be mounted onto a horizontally-oriented shaftvia a shaft collar clamping system. In this manner, the user would slidea female collar of the saw base onto a male shaft of the clamp base,then tighten a clamp to affix the position of the two componentstogether. This is depicted in FIGS. 26A-26C. Specifically, FIGS. 26A-26Cillustrate an embodiment of a shaft clamp connection assembly 290 inassociation with a saw joint assembly in accordance with the presentsubject matter. In this version, the clamp base 20 includes a male shaftmember 292, about which is positioned a female collar 294 associatedwith the saw base 40. The female collar 294 is circumferentiallyadjustable via an adjusting member 296. A threaded engagement 297 can beutilized such that rotation of the member 296 about its longitudinalaxis results in size adjustment of the collar 294 about the shaft 292.

Toggle clamps can similarly be used to draw and hold the saw base to theclamp base. These toggle clamps could be configured over center toachieve a latching mechanism, or drawn to a certain position to reachclamp action. This is shown in FIGS. 27A-27D. Specifically, FIGS.27A-27D illustrate an embodiment of a toggle clamp assembly 300 inaccordance with the present subject matter. The toggle clamp assembly300 is used to releasably engage the saw base 40 to the clamp base 20.The toggle clamp assembly 300 includes one or more toggle clamps 302.The toggle clamps 302 are typically affixed to the clamp base 20 and arereleasably engageable with the saw base 40. In many versions, the toggleclamps 302 engage the saw base 40 at landings 304. The toggle clampsmove over center to lock in position and hold the saw base to the clampbase. FIG. 27B shows a hook 301 that the toggle clamp 302 engages intension to draw the joint tight. FIG. 27C shows how the hook 301 couldbe positioned on the saw base 40 to allow the clamp base, mounted overcenter to engage the toggle clamp 302. FIG. 27D shows two toggle clamps302, attached to the clamp base 20, that engage hooks 301 on each end ofthe saw base. The saw base 40 is set onto the clamp base 20 and alignedvia a pin 303 of the clamp base 20 that passes through a slot 305 in thesaw base 40, then the system is tightened together via the toggle clamps302 on the hooks 301 present on the saw base 40.

Cam locking knobs can be positioned such that a male feature in theclamp base is engaged when the knob, integral to the saw base, isrotated. The cam profile would then draw the saw base and clamp basetogether and hold the components in position with adequate force. Thisis shown in FIGS. 28A-28I. Specifically, FIGS. 28A-28I illustrate anembodiment of a cam locking knob assembly 310 in accordance with a sawjoint assembly of the present subject matter. The cam locking knobassembly 310 comprises one or more adjustable cam assemblies 312 havinga member 314 with a positionable cam 316. As will be understood, themember 314 and cam 316 are affixed or secured to one of the clamp base20 or the saw base 40. Upon rotating or otherwise selectivelypositioning the cam 316 via the member 314, the cam 316 contacts one ofthe clamp base 20 or the saw base 40 and secures the bases together 20,40. An eccentric cam provides a force between the saw base and clampbase, holding them together.

Similar to the noted cam locking-knobs, a cam-profile knob can be usedto grip the saw base to the clamp base when rotated, as shown in FIGS.29A-29B. Specifically, FIGS. 29A-29B illustrate an embodiment of a camprofile knob 320. The cam profile knob 320 includes a cam member 322.One or more cam profile knobs 320 can be used to releasably engage thesaw base 40 to the clamp base 20. As will be understood, rotation of thecam profile knob 320 as shown in FIG. 29B causes engagement between thebases 20, 40.

Two cam-locking knobs can be used to hold the position of the saw baseto the clamp base by engaging the cam into a female slot on the saw basevia a link between the actuation handle and the cam pins, as shown inFIGS. 30A-30B. FIGS. 30A-30B illustrate a twin cam locking knob assembly330 in association with a clamp base 20 and a saw base 40. The twin camlocking knob assembly 330 includes two cam locking assemblies 332secured to the clamp base 20 and a linkage assembly 334 connecting thecam locking assemblies 332. Upon engagement and desired positioning ofthe bases 20, 40, a handle or other member is displaced to translate thelinkage 334 and position the cam locking assemblies 332. Morespecifically, the saw base includes slots 331 which are sized andlocated to receive corresponding cams 333 of the cam locking assemblies332. A user places the saw base 40 onto the clamp base 20. The user thenmoves or otherwise displaces the saw base 40 towards the cam lockingassemblies 332 as shown in FIG. 30B. The user then actuates the linkageassembly 334 and/or the cam locking assemblies 332 to thereby engage thecams 333 with their slots 331. This securely affixes the saw base 40 tothe clamp base 20.

An oval cam knob can also act as a stop for spring pins that engagealignment/lock holes in the mating base. By rotating the knob 90degrees, the spring pins will engage or disengage to clamp or free thesaw base to/from the clamp base. A detent can optionally be used to holdthe position. This is shown in FIGS. 31A-31D. Specifically, FIGS.31A-31D illustrate an embodiment of an oval cam knob assembly 340 inaccordance with the present subject matter. The oval cam knob assembly340 comprises a selectively positionable cam knob 342 secured to the sawbase 40 and one or more, and typically a plurality of spring biasedmembers 344 associated with the clamp base 20. The cam knob 342 definesone or more recessed receiving regions 346 adapted for promotinggripping by a user. The cam knob 342 includes a cam member 347. The camknob 342 may optionally include a detent 348 as noted.

Similar to the various cam assemblies described herein, a spring loadedlever can be used engage a locking pin between the saw base and clampbase. See FIGS. 32A-32B. Specifically, FIGS. 32A-32B illustrate anembodiment of a spring loaded lever assembly 350 for engaging a saw base40 and a clamp base 20, in accordance with the present subject matter.The assembly 350 comprises one or more and typically a plurality oflocking pins 352 which are axially positionable via a linkage assembly354. The locking pins 352 upon axial displacement, engage receivingregions 356 in the clamp base 20. A spring or biasing member 358 can beused to bias the pins 352 to an outwardly projecting engagement positionas shown in FIG. 32A.

Likewise, similar actuation can be achieved through rotating a knob thatmoves a linkage lever and engages or disengages the locking pins, asshown in FIG. 33. Specifically, FIG. 33 illustrates an embodiment of aspring loaded knob assembly 360 used in an assembly of a clamp base 20and a saw base 40, in accordance with the present subject matter. Theassembly 360 comprises a rotatable knob 361, one or more and typically aplurality of locking pins 362 which are axially positionable via alinkage assembly 364. The knob 361 defines slots 363 within which guidepins 365 are retained. The guide pins 365 are integral or affixed to thelocking pins 362. As will be understood, as the knob 361 is rotated, themovement draws the guide pins 365 via their retention in the slots 363.Movement of the guide pins 365 results in movement of the locking pins362. The locking pins 362 upon axial displacement, engage receivingregions 366 in the clamp base 20. A spring or biasing member 368 can beused to bias the pins 362 to an outwardly projecting engagementposition. In certain versions, the assembly 360 is integral to the sawand base and the locking pins 362 engage the receiving regions 366 inthe clamp base 20 to hold the components together.

Another embodiment is to utilize a quick release pin with an integralcam profile that engages a pin/tab on the clamp base. When turned orotherwise positioned, the pin/tab changes the axial position of the pin.The cam profile is configured such that the spring force holds the pinin position during tool use, preventing inadvertent separation. SeeFIGS. 34A-34B. Specifically, FIGS. 34A-34B illustrate an embodiment of aspring biased quick release pin assembly 370 for releasably engaging aclamp base 20 with a saw base 40. The assembly 370 comprises one, andtypically a plurality of, quick release pin(s) 372 with a groove orhelical channel 375 retained with the saw base. Corresponding receivingregions 374 are provided in the clamp base 20. Each receiving region 374includes one or more fingers 376. Upon positioning of a pin 372 inregion 374 and engagement between the finger 376 and groove 375, thebases 20, 40 can be tightened together by rotation of the pin 372 asshown in FIG. 34B. The assembly 370 may optionally include a spring 378or other biasing member.

With most of the embodiments described herein, a hook can be used tolocate and lock one end of the saw base to the clamp base, therebyreducing the number of inputs required from the user when trying to lockor unlock the saw to/from the clamp. See FIGS. 35A-35C. Specifically,FIGS. 35A-35C illustrate an embodiment of a hook assembly 380 inassociation with a saw base 40 and a clamp base 20, in accordance withthe present subject matter. The hook assembly 380 includes at least onehook member 382 projecting from the clamp base 20. The hook 382 extendsthrough an aperture 384 defined in the saw base 40.

A significant benefit of the present subject matter is its efficiencyand ease of use. The setup of the saw and clamp system to the pipe issimplified through the use of the quick connection embodiments, whileretaining the accurateness desired to improve efficiency compared toother steel pipe fabrication methods currently employed. Allowingseparation of the saw from the clamping components improves a user'sability to install onto the workpiece and reduces physical effortrequired.

The chip deflector and/or the chip management system improvescleanliness during the cutting process and reduces clean-up timerequired after completing the cut. This provides additional efficiencyin the fabrication process.

Saws or Pipe Fabrication Tools

A wide array of tools and particularly cutting tools such as poweredpipe fabrication tools or cutting saws can be used with the clampingsystems and/or accessories described herein. Typically, the cuttingtools include a rotary cutting blade driven by an electric motor. Thecutting tools can be in the form of an integral electrically poweredrotary blade saw that is engaged to the clamping system. Examples ofsuch saws are those available from Exact Tools under the designationEXACT SAW. In other applications, the cutting tools can be in the formof a rotary blade saw that is driven by a separable electrically powereddrive. Examples of this latter system include a Model 258 (or 258XL)Power Pipe Cutter and Number 700 Power Drive, available from Ridge Toolunder the RIDGID designation. It will be understood that the presentsubject matter can be used with a wide array of cutting tools and/orsaws. Non-limiting examples of tools include pipe fabrication tools,bevellers, grinders, cutting or grinding wheeled tools, and the like. Itwill be understood that the saws or tools of the present subject matterinclude one or more of the accessories described herein.

FIGS. 36 and 37 illustrate an embodiment of a saw assembly 100 inaccordance with the present subject matter. The saw assembly 100comprises a body or enclosure 104 generally housing an electric motor105 and a gearbox 106 that transfers rotary power from the motor to asaw blade 101. A clutch may optionally be provided between the gearboxand the blade. The saw assembly 100 also comprises one or more handle(s)107 for facilitating gripping and positioning the saw 100 by a user. Thesaw assembly 100 also comprises control provisions to control operationof the saw such as a lock-on switch which can be in the form of anactuator that is depressed to turn the motor 105 on, and a separatebutton to turn the motor 105 off. A variable position trigger switch canbe used to adjust motor speed and thus blade rotary speed. Typical bladespeeds are within a range of from about 1500 rpm to about 5000 rpm orgreater. Although the saws and tools are typically powered by anelectric motor, the present subject matter includes the use of pneumaticor hydraulic power source. Also, the present subject matter includestools and assemblies devoid of a gearbox or transmission.

FIGS. 36 and 37 additionally illustrate the saw assembly 100 with thepreviously described receiving aperture 102 and concave cutout 116 ofthe latch plate 110 (not visible) which engages the quick connect pin 70(not shown). The saw assembly 100 is also depicted as including thepreviously described alignment plate 120 of the plunge guide assembly.The saw assembly 100 also includes the previously described interlocksystem 130 (not visible). The saw assembly 100 also includes thepreviously described blade guard system 150 having a forward blade guard152 and a rearward blade guard 154. The saw assembly 100 also comprisesthe previously described chip management system 160 (not visible). Aspreviously noted, the saw assembly 100 can utilize one or more, or all,of these features. In a particular version, the saw assembly includesthe noted alignment plate in which the alignment plate is adapted toengage a guide on the clamp system, or vice versa. This configurationserves to direct path of the saw by maintaining alignment.

FIGS. 38 and 39 illustrate the saw assembly 100 from FIGS. 36 and 37.FIGS. 38 and 39 illustrate the saw assembly 100 releasably engaged withthe previously described clamping system 2 via the clamp and saw jointassembly 10. FIGS. 38 and 39 also depict the clamping system 2 used inassociation with a frame assembly 2F. Details of the clamping system andnoted frame assembly are set forth in U.S. application Ser. No.16/591,753 filed Oct. 3, 2019. FIGS. 38 and 39 further illustrate theclamping system 2 engaging a workpiece 4 and the saw assembly in a“ready” position. These figures also illustrate additional features ofthe previously described receiving aperture 102 and quick connect pin70; and the alignment plate 120 and its slideable engagement with thegrooved guide 90 of the clamping system 2.

FIGS. 40 and 41 illustrate the saw assembly 100, the clamping system 2,the frame assembly 2F, and the clamp and saw joint assembly 10 fromFIGS. 38 and 39 in which the saw assembly is in a “plunged” positionrelative to the workpiece 4.

In some embodiments, the pipe fabrication tool is a saw using a brushedmotor and connected to external mains-power via a cord. In furtherembodiments, the tool could be used to bevel the pipe, cut a groove inthe surface of the pipe wall, clean or deburr the pipe, thread the pipe,or otherwise prep the pipe for further use. In even further embodiments,the tool could be powered by an integrated or removably battery and usea brushless motor.

In some embodiments, the pipe fabrication tool includes a motor thatuses control electronics and hall sensors. In certain embodiments, themotor is a brushless DC (BLDC) motor. In some embodiments the pipefabrication tool includes internal memory and is capable of storingfunctional parameters such as speed, current values, run time, number ofactuations, and related data.

Many other benefits will no doubt become apparent from futureapplication and development of this technology.

All patents, applications, standards, and articles noted herein arehereby incorporated by reference in their entirety.

The present subject matter includes all operable combinations offeatures and aspects described herein. Thus, for example if one featureis described in association with an embodiment and another feature isdescribed in association with another embodiment, it will be understoodthat the present subject matter includes embodiments having acombination of these features.

As described hereinabove, the present subject matter solves manyproblems associated with previous strategies, systems and/or devices.However, it will be appreciated that various changes in the details,materials and arrangements of components, which have been hereindescribed and illustrated in order to explain the nature of the presentsubject matter, may be made by those skilled in the art withoutdeparting from the principle and scope of the claimed subject matter, asexpressed in the appended claims.

What is claimed is:
 1. A powered cut-off tool comprising: an electricmotor; a rotary cutting blade driven by the motor; control provisionsfor selectively adjusting operation of the motor; at least one featureselected from the group consisting of: (i) an alignment plate for use ina plunge guide assembly, (ii) a latch plate assembly for use in a quickconnection assembly, (iii) an interlock system, (iv) a blade guardsystem, (v) a chip management system, and (vi) combinations of (i)-(v).2. The powered cut-off tool of claim 1 wherein the saw comprises feature(i), the alignment plate adapted to slidably engage a grooved guide ofthe plunge guide assembly.
 3. The powered cut-off tool of claim 1wherein the saw comprises feature (ii), the latch plate assemblyincluding a positionable latch plate provided on the saw, the latchplate defining a concave cutout, the saw including a receiving aperture,wherein upon insertion of a quick connect pin in the receiving aperture,the concave cutout of the latch plate engages the quick connect pin. 4.The powered cut-off tool of claim 1 wherein the saw comprises feature(iii), the interlock system including an electrical switch and areceiving aperture in the saw, wherein upon insertion of a quick connectpin in the receiving aperture, the electrical switch is closed tothereby allow operation of the saw.
 5. The powered cut-off tool of claim1 wherein the saw comprises feature (iv), the blade guard including aforward blade guard positionable about an axis of rotation of the blade,and a rearward blade guard also positionable about the axis of rotationof the blade.
 6. The powered cut-off tool of claim 1 wherein the sawcomprises feature (v), the chip management system including: a bladeguard positioned adjacent the rotary blade of the saw, the blade guardincluding an exit and at least one diverging wall extending toward theexit; at least one primary channel defined in the saw extending betweenthe exit of the blade guard and a region in the saw for dispellingchips.
 7. A quick release assembly for attaching a pipe fabrication toolto a clamping system, the clamping system including a pair of pivotallymoveable arms and a slideable central carriage, the quick releaseassembly comprising: a quick connect pin extending outward from theclamping system, the pin defining a tip, a base, and a circumferentialgroove extending about an outer periphery of the pin.
 8. The quickrelease assembly of claim 7 further comprising: a positionable latchplate provided on the pipe fabrication tool, the latch plate defining aconcave cutout adapted to engage the quick connect pin upon positioningthe latch plate to an engaged position.
 9. The quick release assembly ofclaim 8 wherein upon positioning the latch plate to the engagedposition, the latch plate cutout is disposed in the circumferentialgroove of the quick connect pin.
 10. The quick release assembly of claim7 wherein the quick connect pin defines a first circumferential regionhaving a first diameter D₁, a tapered transition region, and a secondcircumferential region having a second diameter D₂, wherein the seconddiameter D₂ is greater than the first diameter D₁.
 11. The quick releaseassembly of claim 7 further comprising: a plunge guide assemblyincluding (i) a grooved guide affixed to the clamping system, and (iii)an alignment plate affixed to the pipe fabrication tool; wherein one ofthe grooved guide and the alignment plate includes an axiallypositionable pin, and the other of the grooved guide and the alignmentplate includes a cylindrical bore; wherein upon attaching the pipefabrication tool to the clamping system, the alignment plate is engagedwith the grooved guide by axial positioning of the pin in thecylindrical bore.
 12. The quick release assembly of claim 7 wherein thepipe fabrication tool defines a receiving aperture sized and shaped toreceive and accept the quick connect pin, the quick release assemblyfurther comprising: an interlock system including an electrical switch,wherein upon insertion of the quick connect pin in the receivingaperture, the electrical switch is closed to thereby allow operation ofthe pipe fabrication tool.
 13. The quick release assembly of claim 12wherein the interlock system further includes a positionable paddle andwherein upon insertion of the quick connect pin in the receivingaperture, the paddle is positioned to thereby cause closure of theelectrical switch.
 14. The quick release assembly of claim 7 wherein thepipe fabrication tool includes a rotary blade, the quick releaseassembly further comprising: a blade guard system including a forwardblade guard positionable about an axis of rotation of the blade, and arearward blade guard also positionable about the axis of rotation of theblade.
 15. The quick release assembly of claim 14 wherein both of theforward blade guard and the rearward blade guard are biased to a closedposition to reduce access to the blade.
 16. The quick release assemblyof claim 7 further comprising: a chip deflector secured to the clampingsystem, the chip deflector including at least one wall for contactingand redirecting metal chips.
 17. A plunge guide assembly for use with apipe fabrication tool having a rotary blade, and a clamping system, theplunge guide assembly comprising: an alignment plate affixed to the pipefabrication tool; a grooved guide affixed to the clamping system;wherein one of the grooved guide and the alignment plate includes anaxially positionable pin, and the other of the grooved guide and thealignment plate includes a cylindrical bore; wherein upon attaching thepipe fabrication tool to the clamping system, the alignment plate isengaged with the grooved guide by axial positioning of the pin in thecylindrical bore.
 18. A latch plate assembly for use with a pipefabrication tool having a rotary blade and defining a receivingapertures, and a clamping system having a quick connect pin extendingoutward from the clamping system, the pin defining a circumferentialgroove extending about an outer periphery of the pin, the latch plateassembly comprising: a positionable latch plate provided on the pipefabrication tool, the latch plate defining a concave cutout; whereinupon insertion of the quick connect pin in the receiving aperture, theconcave cutout of the latch plate engages the quick connect pin.
 19. Aninterlock system for use with a pipe fabrication tool having a rotaryblade and defining a receiving aperture, and a clamping system having aquick connect pin extending outward from the clamping system, theinterlock system comprising: an electrical switch, wherein uponinsertion of the quick connect pin in the receiving aperture, theelectrical switch is closed to thereby allow operation of the pipefabrication tool.
 20. The quick release assembly of claim 19 wherein theinterlock system further includes a positionable paddle and wherein uponinsertion of the quick connect pin in the receiving aperture, the paddleis positioned to thereby cause closure of the electrical switch.
 21. Achip management system for use with a pipe fabrication tool having arotary blade, the chip management system comprising: a blade guardpositioned adjacent the rotary blade of the pipe fabrication tool, theblade guard including an exit and at least one diverging wall extendingtoward the exit; at least one primary channel defined in the pipefabrication tool extending between the exit of the blade guard and aregion in the pipe fabrication tool for dispelling chips generatedduring blade operation.
 22. The chip management system of claim 21further comprising: a secondary channel defined in the pipe fabricationtool and extending between (i) a port providing chip flow communicationbetween the at least one primary channel and the secondary channel, and(ii) a region in the pipe fabrication tool for dispelling chipsgenerated during blade operation.
 23. The chip management system ofclaim 22 further comprising: a deflection door on the pipe fabricationtool, the door selectively positionable to provide access to at leastone of the port and the secondary channel.
 24. A blade guard system foruse with a pipe fabrication tool having a rotary blade, the blade guardsystem including a forward blade guard positionable about an axis ofrotation of the blade, and a rearward blade guard also positionableabout the axis of rotation of the blade.
 25. The blade guard system ofclaim 24 wherein both of the forward blade guard and the rearward bladeguard are biased to a closed position to reduce access to the blade.